We do PCIe compliance test by following Document “Jetson AGX Xavier Series Tuning and Compliance Guide DA-09855-001_v1.3” - Section “Jetson AGX Xavier PCIe Compliance Testing Reference” - Page 27.
When we tried to access the register “0x14160004” or “0x141A0004”
using devmem2 and busybox devmem tools
we get the following output from a remote terminal:
agx@ubuntu:~$ sudo devmem2 0x14160004
/dev/mem opened.
Memory mapped at address 0x7f9d299000.
Bus error
From a local terminal, the last register value print to the command-line is not visible.
There is a sudden freeze and than the crash/restart.
Our system with a custom baseboard with SDK 4.6.
But I got the same result from our AGX Xavier development kit with SDK 4.6.3 with the following logs (attached): lspci.log (1.6 KB) dmesg.log (73.7 KB)
We encountered the problem on our custom board with SDK 4.6.
Later, we tried the same with the AGX Xavier developer kit
without any modification to the original image from SDK 4.6.3.
The result was the same.
The problem occurs with PEX x1 register modification.
I assume there is some problem with 0x14160004.
For PEX x4 it seems working.
Its address is 0x141A0004.
Please see the page below:
Document “Jetson AGX Xavier Series Tuning and Compliance Guide DA-09855-001_v1.3” - Section “Jetson AGX Xavier PCIe Compliance Testing Reference” - Page 27.